1. Field of the Invention
The present invention generally relates to marine watercrafts and more specifically to outboard engine enclosures for marine watercrafts.
2. Description of Related Art
Marine watercrafts incorporate various means of propulsion including but not limited to internal combustion engines. Such engines are typically powered by a fossil fuel such as a gasoline and are configured to drive a driveshaft to which a propeller is connected. The engine therefore turns the propeller and the propeller converts the rotational power into thrust. More specifically, a pressure differential is produced between the forward and rear surfaces of the airfoil-shaped propeller, and the water is accelerated behind the blade. Marine watercrafts can utilize one or more engines depending on the size and configuration of the watercraft and desired power characteristics. For example, a small leisure craft may only require a small single engine while a large cruise liner may require several larger engines in order to provide optimal thrust and power output.
Marine watercrafts can be configured to operate with several styles of engines including, but not limited to, outboard motors, inboard motors, and inboard/outboard motors also known as stern drive motors. Outboard marine motors comprise a self-contained unit that includes engine, gearbox, and propeller or jet drive, designed to be affixed to the outside of the transom or rear platform of the watercraft. An inboard motor is an motor system wherein the engine and gearbox are mounted inside the hull of the watercraft whereby a driveshaft connects the external propeller to the gearbox. An inboard/outboard motor or “sterndrive” motor combines inboard power with outboard drive wherein the engine itself sits just forward of the transom while the drive unit lies outside the hull.
In the case of outboard marine motors, the motor also provides a means for steering the watercraft as the outboard motor is designed to pivot over its mountings and thus control the direction of thrust. Often times multiple outboard motors are provided on a watercraft to increase power output. These multiple outboard motors are typically linked at their mountings such that the motors pivot simultaneously in order to steer the watercraft. In addition to pivoting, outboard motors are also configured to tilt upward and downward to control the depth to which the propeller reaches. This allows the watercraft operator to traverse waters of varying depth in that the motor can be tilted upward to provide clearance in shallow waters. In the case of mid-size to large outboard powered watercrafts, the motor is typically bolted to the transom of the watercraft and is linked to controls at the helm. Such controls are often electronic and include one or more throttles, steering controls, and tilt controls.
Compared to inboard motors or stern drive motors, outboard motors have several advantages including smaller footprint, increased available cabin and cockpit space, improved simplicity, easier maintenance, easier replacement/retrofitting, and enhanced modularity. It is for these reasons that outboard motors are preferred for pleasurecraft and sport fishing boats. That being said, outboard motors have the disadvantage that the motor must be externally mounted to the transom of the watercraft. This can rob the rear of the watercraft of usable space for recreational activities such as swimming, diving, and fishing. Furthermore, the appearance of outboard motors is considered unsightly to some because the large powerhead and midsection of the motor is obtrusively visible at the stern of the watercraft. While there have been advancements in the overall aesthetics of outboard motors, there is a desire to provide a means to conceal the motors while still providing the several aforementioned advantages that outboard motors provide.
There have been some attempts at improving the aesthetics of marine watercrafts with respect to engine configurations, but none have adequately solved the problems outlined above. For example, U.S. Patent Application No. 2012/0115376 to Daikoku et al. describes an engine case that houses the engine inside and provides a propulsion unit outside of the case. The case's main compartment covers the engine parts and includes an opening at the upper rear portion through which the propulsion parts extent. Mufflers are installed on the lower surface of the case. The case is designed to mount to the transom of a watercraft such as an inflatable boat. The design is limited, however, in that it does not allow for the use of conventional outboard motors and the case does not provide an optimal environment for the motor with respect to temperature and moisture.
U.S. Pat. No. 7,413,492 provides a watercraft with a modular inboard/outboard motor configuration wherein a housing in the hull of the watercraft is adapted to completely enclose an engine with a drive shaft and propeller extending rearward to the transom. Essentially this system provides for a removable inboard engine. While this system allows for easier re-powering, it fails to provide the general benefits of outboard motors in that service access to the engine compartment is compromised.
It is, therefore, to the effective resolution of the aforementioned problems and shortcomings of the prior art that the present invention is directed. However, in view of the outboard-powered marine watercrafts in existence at the time of the present invention, it was not obvious to those persons of ordinary skill in the pertinent art as to how the identified needs could be fulfilled in an advantageous manner.